---
id: "CVE-2026-66281"
kind: "vulnerability"
aliases: ["CVE-2026-66281"]
title: "EmberZNet: malformed Discover Attributes command causes infinite loop on device"
severity: "medium"
cvss: 6.0
epss: 0.00219
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["embedded", "emberznet", "infrastructure", "iot", "zigbee"]
not_affected_if: ["no-manufacturer-specific-clusters", "no-untrusted-joined-devices"]
published_at: "2026-10-22T14:17:43+00:00"
first_seen_at: "2026-10-23T21:57:31+00:00"
updated_at: "2026-10-25T04:05:27+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66281", "first_seen_at": "2026-10-23T21:57:31+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-66281", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# EmberZNet: malformed Discover Attributes command causes infinite loop on device

A malformed Discover Attributes command in EmberZNet 9.1.1 and earlier puts the device into a loop with no reachable exit, which hangs it. Only devices that support manufacturer-specific clusters are impacted, and the message has to come from a device already joined to the network.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the EmberZNet SDK version in the project (unknown exact command from sources)
- Confirm whether the device firmware uses manufacturer-specific clusters (unknown from sources)

## Fix

- Move to a fixed EmberZNet release newer than `9.1.1` (fixed version unknown from sources)

## Timeline

- 2026-10-23T21:57:31+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-66281
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-66281

## From the sources

In EmberZNet 9.1.1 and earlier, a malformed Discover Attributes command can result in a loop with unreachable exit condition (infinite loop). These messages must come from a device that has already joined the network. Only devices supporting manufacturer-specific clusters are impacted.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_